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Scientists Create Mice With Two Fathers After Making Eggs From Male CellsPosted by BeauHD on Thursday March 09, 2023 @05:00AM from the XY-to-XX dept.Scientists have created mice with two biological fathers by generating eggs from male cells, a development that opens up radical new possibilities for reproduction. The Guardian reports:CitarThe advance could ultimately pave the way for treatments for severe forms of infertility, as well as raising the tantalizing prospect of same-sex couples being able to have a biological child together in the future. "This is the first case of making robust mammal oocytes from male cells," said Katsuhiko Hayashi, who led the work at Kyushu University in Japan and is internationally renowned as a pioneer in the field of lab-grown eggs and sperm. Hayashi, who presented the development at the Third International Summit on Human Genome Editing at the Francis Crick Institute in London on Wednesday, predicts that it will be technically possible to create a viable human egg from a male skin cell within a decade. Others suggested this timeline was optimistic given that scientists are yet to create viable lab-grown human eggs from female cells.The study, which has been submitted for publication in a leading journal, relied on a sequence of intricate steps to transform a skin cell, carrying the male XY chromosome combination, into an egg, with the female XX version. Male skin cells were reprogrammed into a stem cell-like state to create so-called induced pluripotent stem (iPS) cells. The Y-chromosome of these cells was then deleted and replaced by an X chromosome "borrowed" from another cell to produce iPS cells with two identical X chromosomes. "The trick of this, the biggest trick, is the duplication of the X chromosome," said Hayashi. "We really tried to establish a system to duplicate the X chromosome."Finally, the cells were cultivated in an ovary organoid, a culture system designed to replicate the conditions inside a mouse ovary. When the eggs were fertilized with normal sperm, the scientists obtained about 600 embryos, which were implanted into surrogate mice, resulting in the birth of seven mouse pups. The efficiency of about 1% was lower than the efficiency achieved with normal female-derived eggs, where about 5% of embryos went on to produce a live birth. The baby mice appeared healthy, had a normal lifespan, and went on to have offspring as adults. "They look OK, they look to be growing normally, they become fathers," said Hayashi. He and colleagues are now attempting to replicate the creation of lab-grown eggs using human cells.
The advance could ultimately pave the way for treatments for severe forms of infertility, as well as raising the tantalizing prospect of same-sex couples being able to have a biological child together in the future. "This is the first case of making robust mammal oocytes from male cells," said Katsuhiko Hayashi, who led the work at Kyushu University in Japan and is internationally renowned as a pioneer in the field of lab-grown eggs and sperm. Hayashi, who presented the development at the Third International Summit on Human Genome Editing at the Francis Crick Institute in London on Wednesday, predicts that it will be technically possible to create a viable human egg from a male skin cell within a decade. Others suggested this timeline was optimistic given that scientists are yet to create viable lab-grown human eggs from female cells.The study, which has been submitted for publication in a leading journal, relied on a sequence of intricate steps to transform a skin cell, carrying the male XY chromosome combination, into an egg, with the female XX version. Male skin cells were reprogrammed into a stem cell-like state to create so-called induced pluripotent stem (iPS) cells. The Y-chromosome of these cells was then deleted and replaced by an X chromosome "borrowed" from another cell to produce iPS cells with two identical X chromosomes. "The trick of this, the biggest trick, is the duplication of the X chromosome," said Hayashi. "We really tried to establish a system to duplicate the X chromosome."Finally, the cells were cultivated in an ovary organoid, a culture system designed to replicate the conditions inside a mouse ovary. When the eggs were fertilized with normal sperm, the scientists obtained about 600 embryos, which were implanted into surrogate mice, resulting in the birth of seven mouse pups. The efficiency of about 1% was lower than the efficiency achieved with normal female-derived eggs, where about 5% of embryos went on to produce a live birth. The baby mice appeared healthy, had a normal lifespan, and went on to have offspring as adults. "They look OK, they look to be growing normally, they become fathers," said Hayashi. He and colleagues are now attempting to replicate the creation of lab-grown eggs using human cells.
Avalancha de hombres que piden el cambio de sexoPrimera semana de la Ley Trans. El elevado volumen de solicitudes de varones hace sospechar en los registros civiles un intento de sacar provecho del nuevo génerohttps://www.larazon.es/sociedad/avalancha-hombres-que-piden-cambio-sexo_20230310640a806531c73f00015ad65e.html
Las apps lo arreglarán todo. Innovamat levanta 20 millones de euros para quitar a los jóvenes el miedo a las matemáticasUna vez más, lo antimolón es dar más medios a los profesores como Wanderer, y lo molón es una app con efectos chulos y gamificación. El CEO se llevará un buen pellizco de la inversión, pero es una pequeña compensación de nada por quitar el miedo a las matemáticas, ¿no? Me juego un café a que el tío ése no ha resuelto una integral en su vida.
Como a mí siempre se me han dado bien las matemáticas, y más allá de clases particulares sueltas no tengo experiencia como docente, se me hace extraño meterme en la problemática de la enseñanza de las matemáticas.Es evidente que hay un "turning point" cuando se empiezan a abordar matemáticas más abstractas. Pasa lo mismo que ocurrió en la historia misma de las matemáticas, surgieron como un intento de describir la realidad (cuentas, longitudes, áreas...). Todo se reflejaba en números enteros y figuras geométricas.Los números negativos eran alienígenas. No digamos ya el cero y los imaginarios cuando se descubrieron. Pero desligar el álgebra de la geometría fue esencial, la realidad opera con muchas más cosas de las que podemos sentir.En este sentido, empezar con ideas informales sobre funciones, límites, y demás, puede ser un buen comienzo. Eso, y tener un profesor competente que no te haga odiar la materia. Pero igualmente llega un momento en que tienes que pasar de las cuentas de la primaria a cuestiones abstractas como límites, que son la base misma del cálculo infinitesimal.Luego, si les hablas a los chavales de los cuaterniones, ya les estalla la cabeza. Hasta que les dices que sin ellos no tendrían Fortnite. El álgebra de cuaterniones es esencial para representar objetos en 3D, es una forma más compacta que una matriz para representar posición y giro. Luego, también está la anécdota de John Carmack cuando encontró una forma mucho más rápida que la conocida hasta entonces para encontrar la inversa de una raíz cuadrada. ¿Y eso qué eh y pa qué sirve? Pues para calcular reflejos en un plano, con lo que se pueden empezar a implementar rebotes de una bala en una pared en un shooter, o reflejos de una fuente de luz.Eso sí, hay una cosa que yo cambiaría seguro en el bachillerato. A los chavales no les puedes enchufar primero todo el tocho de límites, y luego el de derivadas e integrales, porque los tres están relacionados. El concepto de para qué sirve cada cosa es mucho más básico que saberse la tabla de integrales, si yo sé qué es una integral y para qué sirve, me costará menos esfuerzo buscar la integral de una trigonométrica complicada.